Dry-Line Walls

This entry was posted on October 20, 2013 by Stuart.

Skill Level: Intermediate

Introduction

Dry-lining is a method of joining sheets of plasterboard using a special jointing compound and jointing tape, that will give a flat and smooth finish; and which may be decorated over without the need for traditional plastering materials and skills.

Manufactured sheets of paper covered plaster are widely used to “dry-line” both walls and ceilings in modern homes of today. Plasterboard can be nailed to a timber frame that is attached to masonry or brickwork, a stud partition, or bonded straight onto masonry and brickwork using an adhesive or plaster mix. Our project here is the joining and sealing of the vertical joints of the abutted plasterboards. By now we have the boards up, firmly attached to the wall, by whichever means we chose; and it only remains now to seal up the joins between the boards, before decorating.

Covering nails.

The last thing we want when coming to decorate is unsightly bumps showing through the paint or wallpaper.

If the plasterboards have been fixed to a stud partition wall, or are nailed to a timber frame, then the first thing we must do is check over all nailing positions? Fill any indentations (stray hammer marks included) using a filling knife and general purpose filler material. Make sure there are no nails standing proud.

Use a nail Punch to knock the nail heads just below the board surface; but not too far or you may damage the board. Fill these indentations also, and any gaps down the joins to be covered by the jointing tape. When dry, sand down any excess filler.

Jointing Compound.

Jointing compound for dry-lining comes in ready mix, or powder form. The choice is yours.

Mix thoroughly the compound in a bucket, or stir thoroughly where ready mixed, and smooth the compound into the full length of the joint, using a hand scraper or filling knife. Ensure that there is a liberal, but not excessive layer of the compound on the board surface, either side of the joint.

Jointing Tape.

This tape spans the join area and will bridge the gap between two boards.

Cut a piece of jointing tape to the correct length using a pair of scissors, and press down firmly, into the surface jointing compound; covering the whole of the joint from top to bottom.

Coating Knife.

Using the blade of a decorators coating knife, press and smooth down the jointing compound along the taped area so the compound is flush with the surface of the tape. When you are happy you have a nice, neat and smooth jointed area, immediately wipe the surface (carefully) with a damp, clean sponge. Make sure you wring it out thoroughly and frequently; excess water will dilute and weaken the jointing compound.

Feather the Edges.

Using the compound coating knife, spread a wide band of compound down the full length of the joint, then use the damp sponge to feather the edges; you are trying to “blend” the compound into the boards either side of the join.

Internal Corners.

The internal corners on dry-lined walls are finished in exactly the same way as flat joints. First make sure any gaps are made flush by applying filler, once dry, lightly sand down flush. Cut a piece of jointing tape to the required length, and fold down the middle. Next, spread a layer of jointing compound down either side of the corner to be covered; and press the tape into place. Use the compound coating knife to smooth and flatten down, from top to bottom. Once this is dry, apply a second, wider band of compound to the jointed area, over the tape, and feather the edges using a damp sponge.

External Corners.

External corners can take a few more bumps and knocks than other areas of dry-lining, so it is advisable to use a metal reinforced corner tape to cover these areas. The steps to follow are similar to those of internal corners;

Cut the tape to length.

Apply a layer of filler down either side of the plasterboard corner.

Press the tape firmly into place.

Apply a second layer of compound filler over the corner tape, extending over and onto the plasterboards, and feather with a damp sponge.

Dry Wall Primer.

Always coat plasterboards with a primer before decorating.

Priming dry-lined walls serves several purposes. It covers up the colour variations of the plasterboard paper, and the dried plaster. It seals the surface, so that paint may be applied and will be absorbed evenly. It forms a protective barrier to keep out moisture; and in doing so protects the plaster.